package com.example.yuan.interceptor;

import com.alibaba.fastjson.JSONObject;
import com.example.yuan.pojo.Result;
import com.example.yuan.utils.JwtUtils;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@Slf4j
@Component
public class LoginCheckInterceptor implements HandlerInterceptor {
    @Override//目标资源方法运行前运行, 返回true: 放行, 放回false, 不放行
    public boolean preHandle(HttpServletRequest req, HttpServletResponse resp, Object handler) throws Exception {


        //1.获取url
        String url = req.getRequestURL().toString();
        log.info("请求url:{}",url);
        //2.是否包含login请求，包含了放行
        if (url.contains("login")){
            log.info("登录操作，放行");
            return true;
        }
        //3.获取请求头中令牌
        String jwt = req.getHeader("token");
        //4.判断令牌是否存在，不存在返回错误信息
        if (!StringUtils.hasLength(jwt)){
            log.info("请求头token为空");
            Result error = Result.error("NOT_LOGIN");
            //手动转换 对像--json
            String notLogin = JSONObject.toJSONString(error);
            resp.getWriter().write(notLogin);
            return false;
        }
        //5.解析token 如果解析失败，返回错误结果
        try {
            JwtUtils.parseJWT(jwt);
        } catch (Exception e) {
            e.printStackTrace();
            log.info("返回令牌失败");
            Result error = Result.error("NOT_LOGIN");
            //手动转换 对像--json
            String notLogin = JSONObject.toJSONString(error);
            resp.getWriter().write(notLogin);
            return false;
        }//6.放行

        log.info("令牌合法放行");
        return true;
    }

    @Override//目标资源方法运行后运行
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        System.out.println("postHandle ...");
    }

    @Override//视图渲染完毕后运行, 最后运行
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        System.out.println("afterCompletion");
    }
}
